Peters



(No Model.)

P. 9.3mm.

NUT LOGK.- N0. 329,861. Patented Nov. '3, 1 885.

* X Z l mggg gm UNITE FRANK G. STARK, OF NEW YORK, N. Y.

NUT-LOCK.

SPECIFICATIOI}? forming part of Letters Patent No. 329,861, datedNovember 3, 1885.

Application filed February 28, 1885. Serial No. 157,416. (No model.)

To all whom it may concern:

Be it known that I, FRANK G. STARK, of New York city, in the county andState of New York, have invented certain new and useful Improvements inNut-Locks, of which the following is a specification.

I produce a longitudinal groove, sometimes denominated a spline, in thebolt. I make no groove or spline in the nut, but produce a set ofnotches of rectangular section on the back face of the nut, arrangedaround the hole, which is fully screw-threaded, as usual, except at thisnotched end. I provide an implement, which I will term a spring-key,adapted to be inserted in the spline, and to engage by its elasticity inone of the notches in the nut. The key will hold itself in place underall ordinary or extraordinary conditions, so long as no force is appliedwith the intent to remove the key; but when it is desired to unlock thenut a sufficient force applied to move the spring-key endwise willinduce its prompt removal.

The accompanying drawings form a part of this specification, andrepresent what I consider the best means of carrying out the invention.

Figure 1 is a side view; Fig. 2, an end view, and Fig. 3 a longitudinalsection. These figures show parts engaged. Fig. 4 is a longitudinalsection showing the parts in the act of being engaged or released. Fig.5 is a springkey detached. Fig. 6 is a cross-section of the bolt,showing the rear face of the nut in elevation.

Similar letters of reference indicate corresponding parts in the figureswhere they occur.

A is the body of the bolt, and a is a deep spline-groove milled orotherwise produced therein. It will be observed that this groove isconsiderably deeper than the threads of the screw.

B is the nut, and B B a series of notches in one end or face thereof.These notches extend inward only a little distance-say across one threadof the screw.

B B are slight impressions on the opposite faces of the nut, coincidingexactly with the notches B.

D is my spring-key, certain portions being designated, when necessary,by additional marks, as D D One arm, D, of the key is adapted to lie inthe bottom of the spline a.

D isa loop connecting D by an incline, D

with the spring-arm D, which latter is curved, M

as indicated, forming a swell, D, at its free end.

I have in my experiments made all parts of the spring-key-of uniformwidth, a little less than that of the splinegroove a. In such case thenotches B should be of about the same width as the spline; but thiscondition may be varied.

In operating the invention the nut is turned, by a suitable wrench orother means, until it is tightened or is in the position it is desiredit shall maintain. Then the spring-key is inserted in the spline a. Thefaint impressions B serve the function of indicating to the eye theposition of the corresponding notches, B. The spring-key, being properlyentered, may be driven endwise by any suitable force, the swell D ridingunder the several screw-threads in the obvious manner. The length of thekey is such that when it is fully home the swell D coincides with one ofthe notches B in the under face of the nut and by the elasticity of thespring-key engages in such notch and holds firmly. The swell D2 takinghold of the notch, prevents the key from slipping out. The contact ofthe incline D of the loop D with the front face of the nut prevents thekey from moving too far inward. The nut cannot turn on the bolt with thekey in position without shearing the metal of the key. It will remainreliably locked for any length of time. No accidental force, as gravityor concussion, can remove the key. So long as the key remains inposition the nut is locked; but whenever it is desired to liberate thekey it may be drawn out by any suitable hook de vice engaged in the loopD It is important that the swell D" be beveled on both faces andsmoothly finished, so that it can ride under the threads of the nut bothin the act of being inserted and in the act of being removed. Theabsence of longitudinal grooves or splines in the interior of the nutinsures that there is always a proper threaded surface engaged with thepartial threads of the bolt. The

grooves or splines a in the bolt must be sufficiently deep toaccommodate the spring-key entirely below or within the innermost edgesof the threads.

Modifications'may be made in the forms and proportions. I can make theswell D narrower than the main body of the key. In such case narrowernotches B may serve. I can duplicate the splines a in the bolt. Onespline a is sufficient for all ordinary cases.

I am aware that grooves have been made in the threaded portions of bothnut and bolt to receive a spring locking-key; but when the nut-slots arethus located they are either so distant from each other that they impairthe functions of the nut, or, being numerous, they greatly impair thestrength of the nut.

Instead of locating my key-engaging slots in the barrel of the nut, Iplace them upon one of its faces.

. I am aware of English Patents Nos. 1,644 of 1866 and 298 of 1880, inwhich the recesses are made in the bore of the nut.

I claim as my inventionl. The combination, with a nut having radialrecesses upon its inner faces, arranged at approximate right angles withthe bore of the nut, and with a slotted bolt, as shown, of a spring-keyhaving an arm to engage said recesses upon one face of the nut, and anarm to engage the opposite or outer face of the nut and limit the inwardmovement of the key, as set forth.

2. The combination, with a nut having radial recesses B upon one faceand corresponding marks or recesses, B upon the other face, of a slottedbolt and a key having an arm with opposing inclines, as D D to engageopposite recesses upon both faces of the nut, as set forth.

3. The combination, with the nut B, having recesses B arranged upon oneface at approximate right angles to the plane of the bore of v the nut,and with the bolt A, having slot (1-, of

the spring-key having arms DD and the latter provided with arms orinclines D D arranged to engage the nut upon opposite facessimultaneously, as set forth.

In testimony whereof I have hereuntoset my hand, at the city of St.Louis and State of Missouri, this 20th day of February, '1885, in thepresence of two subscribing witnesses.

FRANK G. STARK.

\Vitnesses:

THos. A. RUssELL, E. P. J oHNsoN.

